Functional nucleic acid biosensors utilizing rolling circle amplification.

Functional nucleic acids (FNAs), including DNA aptamers and DNAzymes, are finding increasing use as molecular recognition elements for point-of-care (POC) assays and sensors. An ongoing challenge in the development of FNA-based POC sensors is the ability to achieve detection of low levels of analyte without compromising assay time and ease of use. Rolling circle amplification (RCA) is a leading nucleic acid (NA) isothermal amplification method which can be coupled with FNAs for the ultrasensitive detection of non-NA targets.

Hydrophobic/hydrophilic patterned surfaces for directed evaporative preconcentration.

The deposition of micro- and nanolitre volumes is crucial in sessile droplet microfluidic systems. Several techniques exist for the fabrication of surfaces with patterned wettabilities; however, many of these fabrication techniques are time-consuming and complex. Here, we present a device that allows for deposition of multiple droplets within seconds followed by directed evaporative preconcentration.